diff --git a/guile/mu-guile.c b/guile/mu-guile.c
index 2221819f..a3f4ce5a 100644
--- a/guile/mu-guile.c
+++ b/guile/mu-guile.c
@@ -170,7 +170,7 @@ SCM_DEFINE_PUBLIC (mu_initialize, "mu:initialize", 0, 1, 0,
 				       SCM_UNSPECIFIED);
 
 	/* cleanup when we're exiting */
-	g_atexit (mu_guile_uninit_instance);
+	atexit (mu_guile_uninit_instance);
 
 	return SCM_UNSPECIFIED;
 }
diff --git a/src/mu-cmd-cfind.c b/src/mu-cmd-cfind.c
index 7fa56795..d4cd9aa2 100644
--- a/src/mu-cmd-cfind.c
+++ b/src/mu-cmd-cfind.c
@@ -179,7 +179,7 @@ run_cmd_cfind (const char* pattern, MuConfigFormat format,
 
 	contacts = mu_contacts_new (mu_runtime_path(MU_RUNTIME_PATH_CONTACTS));
 	if (!contacts) {
-		g_set_error (err, 0, MU_ERROR_CONTACTS_CANNOT_RETRIEVE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_CONTACTS_CANNOT_RETRIEVE,
 				     "could not retrieve contacts");
 		return MU_ERROR_CONTACTS_CANNOT_RETRIEVE;
 	}
@@ -234,7 +234,7 @@ mu_cmd_cfind (MuConfig *opts, GError **err)
 			      MU_ERROR_INTERNAL);
 
 	if (!cfind_params_valid (opts)) {
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 			     "invalid parameters");
 		return MU_ERROR_IN_PARAMETERS;
 	}
diff --git a/src/mu-cmd-extract.c b/src/mu-cmd-extract.c
index 275e6f02..fdc8719c 100644
--- a/src/mu-cmd-extract.c
+++ b/src/mu-cmd-extract.c
@@ -401,7 +401,7 @@ mu_cmd_extract (MuConfig *opts, GError **err)
 			      MU_ERROR_INTERNAL);
 
 	if (!check_params (opts)) {
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 				     "error in parameters");
 		return MU_ERROR_IN_PARAMETERS;
 	}
@@ -412,7 +412,7 @@ mu_cmd_extract (MuConfig *opts, GError **err)
 	else {
 		rv = mu_util_check_dir(opts->targetdir, FALSE, TRUE);
 		if (!rv)
-			g_set_error (err, 0, MU_ERROR_FILE_CANNOT_WRITE,
+			g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE_CANNOT_WRITE,
 				     "target '%s' is not a writable directory",
 				     opts->targetdir);
 		else
diff --git a/src/mu-cmd-find.c b/src/mu-cmd-find.c
index 1c788f85..e8de0c65 100644
--- a/src/mu-cmd-find.c
+++ b/src/mu-cmd-find.c
@@ -86,7 +86,7 @@ sort_field_from_string (const char* fieldstr, GError **err)
 		mfid = mu_msg_field_id_from_shortcut(fieldstr[0],
 						     FALSE);
 	if (mfid == MU_MSG_FIELD_ID_NONE)
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 			     "not a valid sort field: '%s'\n", fieldstr);
 	return mfid;
 }
@@ -159,7 +159,7 @@ exec_cmd (const char *path, const char *cmd, GError **err)
 	gboolean rv;
 
 	if (access (path, R_OK) != 0) {
-		g_set_error (err, 0, MU_ERROR_FILE_CANNOT_READ,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE_CANNOT_READ,
 			     "cannot read %s: %s", path, strerror(errno));
 		return FALSE;
 	}
@@ -209,7 +209,7 @@ exec_cmd_on_query (MuQuery *xapian, const gchar *query, MuConfig *opts,
 	}
 
 	if (count == 0) {
-		g_set_error (err, 0, MU_ERROR_NO_MATCHES,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_NO_MATCHES,
 			     "no matches for search expression");
 		return FALSE;
 	}
@@ -231,20 +231,20 @@ format_params_valid (MuConfig *opts, GError **err)
 	case MU_CONFIG_FORMAT_XQUERY:
 		break;
 	default:
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 			     "invalid output format %s",
 			     opts->formatstr ? opts->formatstr : "<none>");
 		return FALSE;
 	}
 
 	if (opts->format == MU_CONFIG_FORMAT_LINKS && !opts->linksdir) {
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 			     "missing --linksdir argument");
 		return FALSE;
 	}
 
 	if (opts->linksdir && opts->format != MU_CONFIG_FORMAT_LINKS) {
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 			     "--linksdir is only valid with --format=links");
 		return FALSE;
 	}
@@ -262,7 +262,7 @@ query_params_valid (MuConfig *opts, GError **err)
 	if (mu_util_check_dir (xpath, TRUE, FALSE))
 		return TRUE;
 
-	g_set_error (err, 0, MU_ERROR_FILE_CANNOT_READ,
+	g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE_CANNOT_READ,
 		     "'%s' is not a readable Xapian directory", xpath);
 	return FALSE;
 }
@@ -277,14 +277,14 @@ resolve_bookmark (MuConfig *opts, GError **err)
 	bmfile = mu_runtime_path (MU_RUNTIME_PATH_BOOKMARKS);
 	bm = mu_bookmarks_new (bmfile);
 	if (!bm) {
-		g_set_error (err, 0, MU_ERROR_FILE_CANNOT_OPEN,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE_CANNOT_OPEN,
 			     "failed to open bookmarks file '%s'", bmfile);
 		return FALSE;
 	}
 
 	val = (gchar*)mu_bookmarks_lookup (bm, opts->bookmark);
 	if (!val)
-		g_set_error (err, 0, MU_ERROR_NO_MATCHES,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_NO_MATCHES,
 			     "bookmark '%s' not found", opts->bookmark);
 	else
 		val = g_strdup (val);
@@ -330,7 +330,7 @@ get_query (MuConfig *opts, GError **err)
 
 	/* params[0] is 'find', actual search params start with [1] */
 	if (!opts->bookmark && !opts->params[1]) {
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 			     "error in parameters");
 		return NULL;
 	}
@@ -368,13 +368,13 @@ get_query_obj (MuStore *store, GError **err)
 		return NULL;
 
 	if (count == 0) {
-		g_set_error (err, 0, MU_ERROR_XAPIAN_IS_EMPTY,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_XAPIAN_IS_EMPTY,
 			     "the database is empty");
 		return NULL;
 	}
 
 	if (mu_store_needs_upgrade (store)) {
-		g_set_error (err, 0, MU_ERROR_XAPIAN_NOT_UP_TO_DATE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_XAPIAN_NOT_UP_TO_DATE,
 			     "the database is not up-to-date");
 		return NULL;
 	}
@@ -468,13 +468,13 @@ output_links (MuMsgIter *iter, const char* linksdir, gboolean clearlinks,
 	}
 
 	if (errcount > 0) {
-		g_set_error (err, 0, MU_ERROR_FILE_CANNOT_LINK,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE_CANNOT_LINK,
 			     "error linking %u message(s)", (unsigned)errcount);
 		return FALSE;
 	}
 
 	if (count == 0) {
-		g_set_error (err, 0, MU_ERROR_NO_MATCHES,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_NO_MATCHES,
 			     "no matches for search expression");
 		return FALSE;
 	}
@@ -686,7 +686,7 @@ output_plain (MuMsgIter *iter, const char *fields, gboolean summary,
 	}
 
 	if (count == 0) {
-		g_set_error (err, 0, MU_ERROR_NO_MATCHES,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_NO_MATCHES,
 			     "no existing matches for search expression");
 		return FALSE;
 	}
@@ -746,7 +746,7 @@ output_sexp (MuMsgIter *iter, gboolean threads,
 	}
 
 	if (count == 0) {
-		g_set_error (err, 0, MU_ERROR_NO_MATCHES,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_NO_MATCHES,
 			     "no existing matches for search expression");
 		return FALSE;
 	}
@@ -803,7 +803,7 @@ output_xml (MuMsgIter *iter, gboolean include_unreadable, GError **err)
 	g_print ("</messages>\n");
 
 	if (count == 0) {
-		g_set_error (err, 0, MU_ERROR_NO_MATCHES,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_NO_MATCHES,
 			     "no existing matches for search expression");
 		return FALSE;
 	}
diff --git a/src/mu-cmd-index.c b/src/mu-cmd-index.c
index 93fee47a..a36db383 100644
--- a/src/mu-cmd-index.c
+++ b/src/mu-cmd-index.c
@@ -75,19 +75,19 @@ check_params (MuConfig *opts, GError **err)
 {
 	/* param[0] == 'index'  there should be no param[1] */
 	if (opts->params[1]) {
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 				     "unexpected parameter");
 		return FALSE;
 	}
 
 	if (opts->xbatchsize < 0) {
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 				     "the batch size must be non-negative");
 		return FALSE;
 	}
 
 	if (opts->max_msg_size < 0) {
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 				     "the maximum message size must be non-negative");
 		return FALSE;
 	}
@@ -99,20 +99,20 @@ static gboolean
 check_maildir (const char *maildir, GError **err)
 {
 	if (!maildir) {
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 			     "no maildir to work on; use --maildir=");
 		return FALSE;
 	}
 
 	if (!g_path_is_absolute (maildir)) {
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 			     "maildir path '%s' is not absolute",
 			     maildir);
 		return FALSE;
 	}
 
 	if (!mu_util_check_dir (maildir, TRUE, FALSE)) {
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 			     "not a valid Maildir: %s", maildir);
 		return FALSE;
 	}
@@ -347,7 +347,7 @@ cmd_index (MuIndex *midx, MuConfig *opts, MuIndexStats *stats,
 		if (rv == MU_STOP)
 			rv = MU_OK;
 	} else
-		g_set_error (err, 0, rv, "error while indexing");
+		g_set_error (err, MU_ERROR_DOMAIN, rv, "error while indexing");
 
 	return rv;
 }
diff --git a/src/mu-cmd-server.c b/src/mu-cmd-server.c
index 53bb7ae1..71711b66 100644
--- a/src/mu-cmd-server.c
+++ b/src/mu-cmd-server.c
@@ -428,7 +428,7 @@ get_docid_from_msgid (MuQuery *query, const char *str, GError **err)
 	docid = MU_STORE_INVALID_DOCID;
 	if (!iter || mu_msg_iter_is_done (iter))
 		if (err && *err == NULL)
-			g_set_error (err, 0, MU_ERROR_NO_MATCHES,
+			g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_NO_MATCHES,
 				     "could not find message %s", str);
 		else
 			return docid;
@@ -436,7 +436,7 @@ get_docid_from_msgid (MuQuery *query, const char *str, GError **err)
 		MuMsg *msg;
 		msg = mu_msg_iter_get_msg_floating (iter);
 		if (!mu_msg_is_readable(msg)) {
-			g_set_error (err, 0, MU_ERROR_FILE_CANNOT_READ,
+			g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE_CANNOT_READ,
 				     "'%s' is not readable",
 				     mu_msg_get_path(msg));
 		} else
@@ -462,7 +462,7 @@ get_docid (MuQuery *query, const char *str, GError **err)
 	docid = strtol (str, &endptr, 10);
 	if (*endptr != '\0') {
 		if (!query) {
-			g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+			g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 				     "invalid docid '%s'", str);
 			return MU_STORE_INVALID_DOCID;
 		} else
@@ -981,7 +981,7 @@ handle_command (Cmd cmd, MuStore *store, MuQuery *query, GSList *args,
 
 	case CMD_IGNORE: return TRUE;
 	default:
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 			     "unknown command");
 		return FALSE;
 	}
diff --git a/src/mu-cmd.c b/src/mu-cmd.c
index ba80e9a2..b10b79e6 100644
--- a/src/mu-cmd.c
+++ b/src/mu-cmd.c
@@ -202,7 +202,7 @@ view_params_valid (MuConfig *opts, GError **err)
 {
 	/* note: params[0] will be 'view' */
 	if (!opts->params[0] || !opts->params[1]) {
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 				     "error in parameters");
 		return FALSE;
 	}
@@ -212,7 +212,7 @@ view_params_valid (MuConfig *opts, GError **err)
 	case MU_CONFIG_FORMAT_SEXP:
 		break;
 	default:
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 				     "invalid output format");
 		return FALSE;
 	}
@@ -264,7 +264,7 @@ mu_cmd_mkdir (MuConfig *opts, GError **err)
 			      MU_ERROR_INTERNAL);
 
 	if (!opts->params[1]) {
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 			     "missing directory parameter");
 		return MU_ERROR_IN_PARAMETERS;
 	}
@@ -320,7 +320,7 @@ mu_cmd_add (MuStore *store, MuConfig *opts, GError **err)
 	/* note: params[0] will be 'add' */
 	if (!opts->params[0] || !opts->params[1]) {
 		g_message ("usage: mu add <file> [<files>]");
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 			     "missing source and/or target");
 		return MU_ERROR_IN_PARAMETERS;
 	}
@@ -339,7 +339,7 @@ mu_cmd_add (MuStore *store, MuConfig *opts, GError **err)
 	}
 
 	if (!allok) {
-		g_set_error (err, 0, MU_ERROR_XAPIAN_STORE_FAILED,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_XAPIAN_STORE_FAILED,
 			     "store failed for some message(s)");
 		return MU_ERROR_XAPIAN_STORE_FAILED;
 	}
@@ -361,7 +361,7 @@ mu_cmd_remove (MuStore *store, MuConfig *opts, GError **err)
 	/* note: params[0] will be 'add' */
 	if (!opts->params[0] || !opts->params[1]) {
 		g_warning ("usage: mu remove <file> [<files>]");
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 				     "missing source and/or target");
 		return MU_ERROR_IN_PARAMETERS;
 	}
@@ -379,7 +379,7 @@ mu_cmd_remove (MuStore *store, MuConfig *opts, GError **err)
 	}
 
 	if (!allok) {
-		g_set_error (err, 0, MU_ERROR_XAPIAN_STORE_FAILED,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_XAPIAN_STORE_FAILED,
 			     "remove failed for some message(s)");
 		return MU_ERROR_XAPIAN_REMOVE_FAILED;
 	}
@@ -438,7 +438,7 @@ check_params (MuConfig *opts, GError **err)
 {
 	if (!opts->params||!opts->params[0]) {/* no command? */
 		show_usage ();
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS, "error in parameters");
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS, "error in parameters");
 		return FALSE;
 	}
 
@@ -476,7 +476,7 @@ mu_cmd_execute (MuConfig *opts, GError **err)
 		return with_store (mu_cmd_server, opts, FALSE, err);
 	default:
 		show_usage ();
-		g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 			     "unknown command '%s'", opts->cmdstr);
 		return MU_ERROR_IN_PARAMETERS;
 	}
diff --git a/src/mu-maildir.c b/src/mu-maildir.c
index 6dc1d819..d867d14f 100644
--- a/src/mu-maildir.c
+++ b/src/mu-maildir.c
@@ -89,7 +89,7 @@ create_maildir (const char *path, mode_t mode, GError **err)
 		 * there's already such a dir, but with the wrong
 		 * permissions; so we need to check */
 		if (rv != 0 || !mu_util_check_dir(fullpath, TRUE, TRUE)) {
-			g_set_error (err, 0, MU_ERROR_FILE_CANNOT_MKDIR,
+			g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE_CANNOT_MKDIR,
 				     "creating dir failed for %s: %s",
 				     fullpath,
 				     strerror (errno));
@@ -115,7 +115,7 @@ create_noindex (const char *path, GError **err)
 	/* note, if the 'close' failed, creation may still have
 	 * succeeded...*/
 	if (fd < 0 || close (fd) != 0) {
-		g_set_error (err, 0, MU_ERROR_FILE_CANNOT_CREATE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE_CANNOT_CREATE,
 			     "error in create_noindex: %s",
 			     strerror (errno));
 		return FALSE;
@@ -208,7 +208,7 @@ mu_maildir_link (const char* src, const char *targetpath, GError **err)
 	rv = symlink (src, targetfullpath);
 
 	if (rv != 0) {
-		g_set_error (err, 0, MU_ERROR_FILE_CANNOT_LINK,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE_CANNOT_LINK,
 			     "error creating link %s => %s: %s",
 			     targetfullpath, src, strerror (errno));
 		g_free (targetfullpath);
@@ -617,7 +617,7 @@ clear_links (const gchar* dirname, DIR *dir, GError **err)
 	}
 
 	if (errno != 0)
-		g_set_error (err, 0, MU_ERROR_FILE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE,
 			     "file error: %s", strerror(errno));
 
 	return (rv == FALSE && errno == 0);
@@ -634,7 +634,7 @@ mu_maildir_clear_links (const gchar* path, GError **err)
 
 	dir = opendir (path);
 	if (!dir) {
-		g_set_error (err, 0, MU_ERROR_FILE_CANNOT_OPEN,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE_CANNOT_OPEN,
 			     "failed to open %s: %s", path,
 			     strerror(errno));
 		return FALSE;
@@ -791,25 +791,25 @@ static gboolean
 msg_move_check_pre (const gchar *src, const gchar *dst, GError **err)
 {
 	if (!g_path_is_absolute(src)) {
-		g_set_error (err, 0, MU_ERROR_FILE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE,
 			     "source is not an absolute path: '%s'", src);
 		return FALSE;
 	}
 
 	if (!g_path_is_absolute(dst)) {
-		g_set_error (err, 0, MU_ERROR_FILE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE,
 			     "target is not an absolute path: '%s'", dst);
 		return FALSE;
 	}
 
 	if (access (src, R_OK) != 0) {
-		g_set_error (err, 0, MU_ERROR_FILE, "cannot read %s",
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE, "cannot read %s",
 			     src);
 		return FALSE;
 	}
 
 	if (access (dst, F_OK) == 0) {
-		g_set_error (err, 0, MU_ERROR_FILE, "%s already exists",
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE, "%s already exists",
 			     dst);
 		return FALSE;
 	}
@@ -822,13 +822,13 @@ msg_move_check_post (const char *src, const char *dst, GError **err)
 {
 	/* double check -- is the target really there? */
 	if (access (dst, F_OK) != 0) {
-		g_set_error (err, 0, MU_ERROR_FILE, "can't find target (%s)",
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE, "can't find target (%s)",
 			     dst);
 		return FALSE;
 	}
 
 	if (access (src, F_OK) == 0) {
-		g_set_error (err, 0, MU_ERROR_FILE, "source is still there (%s)",
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE, "source is still there (%s)",
 			     src);
 		return FALSE;
 	}
@@ -844,7 +844,7 @@ msg_move (const char* src, const char *dst, GError **err)
 		return FALSE;
 
 	if (rename (src, dst) != 0) {
-		g_set_error (err, 0, MU_ERROR_FILE, "error moving %s to %s",
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE, "error moving %s to %s",
 			     src, dst);
 		return FALSE;
 	}
@@ -869,7 +869,7 @@ mu_maildir_move_message (const char* oldpath, const char* targetmdir,
 	newfullpath = mu_maildir_get_new_path (oldpath, targetmdir,
 					       newflags);
 	if (!newfullpath) {
-		g_set_error (err, 0, MU_ERROR_FILE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE,
 			     "failed to determine target full path");
 		return FALSE;
 	}
@@ -878,7 +878,7 @@ mu_maildir_move_message (const char* oldpath, const char* targetmdir,
 	src_is_target = (g_strcmp0 (oldpath, newfullpath) == 0);
 
 	if (!ignore_dups && src_is_target) {
-		g_set_error (err, 0, MU_ERROR_FILE_TARGET_EQUALS_SOURCE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE_TARGET_EQUALS_SOURCE,
 			     "target equals source");
 		return FALSE;
 	}
diff --git a/src/mu-msg-file.c b/src/mu-msg-file.c
index 357339ef..8b0198d9 100644
--- a/src/mu-msg-file.c
+++ b/src/mu-msg-file.c
@@ -100,21 +100,21 @@ init_file_metadata (MuMsgFile *self, const char* path, const gchar* mdir,
 	struct stat statbuf;
 
 	if (access (path, R_OK) != 0) {
-		g_set_error (err, 0, MU_ERROR_FILE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE,
 			     "cannot read file %s: %s",
 			     path, strerror(errno));
 		return FALSE;
 	}
 
 	if (stat (path, &statbuf) < 0) {
-		g_set_error (err, 0, MU_ERROR_FILE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE,
 			     "cannot stat %s: %s",
 			     path, strerror(errno));
 		return FALSE;
 	}
 
 	if (!S_ISREG(statbuf.st_mode)) {
-		g_set_error (err, 0, MU_ERROR_FILE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE,
 			     "not a regular file: %s", path);
 		return FALSE;
 	}
@@ -138,7 +138,7 @@ get_mime_stream (MuMsgFile *self, const char *path, GError **err)
 
 	file = fopen (path, "r");
 	if (!file) {
-		g_set_error (err, 0, MU_ERROR_FILE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE,
 			     "cannot open %s: %s",
 			     path, strerror (errno));
 		return NULL;
@@ -146,7 +146,7 @@ get_mime_stream (MuMsgFile *self, const char *path, GError **err)
 
 	stream = g_mime_stream_file_new (file);
 	if (!stream) {
-		g_set_error (err, 0, MU_ERROR_GMIME,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_GMIME,
 			     "cannot create mime stream for %s",
 			     path);
 		fclose (file);
@@ -169,7 +169,7 @@ init_mime_msg (MuMsgFile *self, const char* path, GError **err)
 	parser = g_mime_parser_new_with_stream (stream);
 	g_object_unref (stream);
 	if (!parser) {
-		g_set_error (err, 0, MU_ERROR_GMIME,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_GMIME,
 			     "%s: cannot create mime parser for %s",
 			     __FUNCTION__, path);
 		return FALSE;
@@ -178,7 +178,7 @@ init_mime_msg (MuMsgFile *self, const char* path, GError **err)
 	self->_mime_msg = g_mime_parser_construct_message (parser);
 	g_object_unref (parser);
 	if (!self->_mime_msg) {
-		g_set_error (err, 0, MU_ERROR_GMIME,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_GMIME,
 			     "%s: cannot construct mime message for %s",
 			     __FUNCTION__, path);
 		return FALSE;
diff --git a/src/mu-msg-part.c b/src/mu-msg-part.c
index 7363dfa3..e0565a06 100644
--- a/src/mu-msg-part.c
+++ b/src/mu-msg-part.c
@@ -337,7 +337,7 @@ write_part_to_fd (GMimePart *part, int fd, GError **err)
 
 	stream = g_mime_stream_fs_new (fd);
 	if (!GMIME_IS_STREAM(stream)) {
-		g_set_error (err, 0, MU_ERROR_GMIME,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_GMIME,
 			     "failed to create stream");
 		return FALSE;
 	}
@@ -345,7 +345,7 @@ write_part_to_fd (GMimePart *part, int fd, GError **err)
 
 	wrapper = g_mime_part_get_content_object (part);
 	if (!GMIME_IS_DATA_WRAPPER(wrapper)) {
-		g_set_error (err, 0, MU_ERROR_GMIME,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_GMIME,
 			     "failed to create wrapper");
 		g_object_unref (stream);
 		return FALSE;
@@ -355,7 +355,7 @@ write_part_to_fd (GMimePart *part, int fd, GError **err)
 
 	rv = g_mime_data_wrapper_write_to_stream (wrapper, stream);
 	if (rv == -1)
-		g_set_error (err, 0, MU_ERROR_GMIME,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_GMIME,
 			     "failed to write to stream");
 
 	g_object_unref (wrapper);
@@ -373,13 +373,13 @@ write_object_to_fd (GMimeObject *obj, int fd, GError **err)
 	str = g_mime_object_to_string (obj);
 
 	if (!str) {
-		g_set_error (err, 0, MU_ERROR_GMIME,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_GMIME,
 			     "could not get string from object");
 		return FALSE;
 	}
 
 	if (write (fd, str, strlen(str)) == -1) {
-		g_set_error (err, 0, MU_ERROR_GMIME,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_GMIME,
 			     "failed to write object: %s",
 			     strerror(errno));
 		return FALSE;
@@ -405,7 +405,7 @@ save_mime_object (GMimeObject *obj, const char *fullpath,
 	/* ok, try to create the file */
 	fd = mu_util_create_writeable_fd (fullpath, 0600, overwrite);
 	if (fd == -1) {
-		g_set_error (err, 0, MU_ERROR_FILE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE,
 			     "could not open '%s' for writing: %s",
 			     fullpath, errno ? strerror(errno) : "error");
 		return FALSE;
@@ -417,7 +417,7 @@ save_mime_object (GMimeObject *obj, const char *fullpath,
 		rv = write_object_to_fd (obj, fd, err);
 
 	if (close (fd) != 0 && !err) { /* don't write on top of old err */
-		g_set_error (err, 0, MU_ERROR_FILE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE,
 			     "could not close '%s': %s",
 			     fullpath, errno ? strerror(errno) : "error");
 		return FALSE;
@@ -438,7 +438,7 @@ mu_msg_part_filepath (MuMsg *msg, const char* targetdir, guint partidx,
 		return NULL;
 
 	if (!(mobj = find_part (msg, partidx))) {
-		g_set_error (err, 0, MU_ERROR_GMIME, "cannot find part %u", partidx);
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_GMIME, "cannot find part %u", partidx);
 		return NULL;
 	}
 
@@ -455,7 +455,7 @@ mu_msg_part_filepath (MuMsg *msg, const char* targetdir, guint partidx,
 		fname  = get_filename_for_mime_message_part
 			(g_mime_message_part_get_message((GMimeMessagePart*)mobj));
 	else {
-		g_set_error (err, 0, MU_ERROR_GMIME, "part %u cannot be saved",
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_GMIME, "part %u cannot be saved",
 			     partidx);
 		return NULL;
 	}
@@ -521,7 +521,7 @@ mu_msg_part_save (MuMsg *msg, const char *fullpath, guint partidx,
 
 	part = find_part (msg, partidx);
 	if (!is_part_or_message_part (part)) {
-		g_set_error (err, 0, MU_ERROR_GMIME,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_GMIME,
 			     "unexpected type %s for part %u",
 			     G_OBJECT_TYPE_NAME((GObject*)part),
 			     partidx);
@@ -540,7 +540,7 @@ mu_msg_part_save_temp (MuMsg *msg, guint partidx, GError **err)
 
 	filepath = mu_msg_part_filepath_cache (msg, partidx);
 	if (!filepath) {
-		g_set_error (err, 0, MU_ERROR_FILE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE,
 			     "Could not get temp filepath");
 		return NULL;
 	}
diff --git a/src/mu-msg.c b/src/mu-msg.c
index 070f8445..59cdc88e 100644
--- a/src/mu-msg.c
+++ b/src/mu-msg.c
@@ -1,6 +1,6 @@
 /* -*- mode: c; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
 **
-** Copyright (C) 2008-2011 Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
+** Copyright (C) 2008-2012 Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
 **
 ** This program is free software; you can redistribute it and/or modify
 ** it under the terms of the GNU General Public License as published by
@@ -93,7 +93,7 @@ mu_msg_new_from_file (const char *path, const char *mdir, GError **err)
 
 	if (G_UNLIKELY(!_gmime_initialized)) {
 		gmime_init ();
-		g_atexit (gmime_uninit);
+		atexit (gmime_uninit);
 	}
 
 	msgfile = mu_msg_file_new (path, mdir, err);
@@ -127,7 +127,7 @@ mu_msg_new_from_doc (XapianDocument *doc, GError **err)
 
 	if (G_UNLIKELY(!_gmime_initialized)) {
 		gmime_init ();
-		g_atexit (gmime_uninit);
+		atexit (gmime_uninit);
 	}
 
 	msgdoc = mu_msg_doc_new (doc, err);
@@ -745,7 +745,7 @@ get_target_mdir (MuMsg *msg, const char *target_maildir, GError **err)
 	/* maildir is the maildir stored in the message, e.g. '/foo' */
 	maildir = mu_msg_get_maildir(msg);
 	if (!maildir) {
-		g_set_error (err, 0, MU_ERROR_GMIME,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_GMIME,
 			     "message without maildir");
 		return NULL;
 	}
@@ -763,7 +763,7 @@ get_target_mdir (MuMsg *msg, const char *target_maildir, GError **err)
 	    /* special case for the top-level '/' maildir, and
 	     * remember not_top_level */
 	    (not_top_level = (g_strcmp0 (maildir, "/") != 0))) {
-		g_set_error (err, 0, MU_ERROR_FILE,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_FILE,
 			     "path is '%s', but maildir is '%s' ('%s')",
 			     rootmaildir, mu_msg_get_maildir(msg),
 			     mu_msg_get_path (msg));
diff --git a/src/mu-query.cc b/src/mu-query.cc
index bac11193..d0d0fe31 100644
--- a/src/mu-query.cc
+++ b/src/mu-query.cc
@@ -213,7 +213,7 @@ get_query (MuQuery *mqx, const char* searchexpr, GError **err)
 
 	} catch (...) {
 		/* some error occured */
-		g_set_error (err, 0, MU_ERROR_XAPIAN_QUERY,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_XAPIAN_QUERY,
 			     "parse error in query");
 		g_free (preprocessed);
 		throw;
@@ -258,7 +258,7 @@ mu_query_new (MuStore *store, GError **err)
 	g_return_val_if_fail (store, NULL);
 
 	if (mu_store_count (store, err) == 0) {
-		g_set_error (err, 0, MU_ERROR_XAPIAN_IS_EMPTY,
+		g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_XAPIAN_IS_EMPTY,
 			     "database is empty");
 		return 0;
 	}
diff --git a/src/mu-store-read.cc b/src/mu-store-read.cc
index 18eb3622..9ced1fc8 100644
--- a/src/mu-store-read.cc
+++ b/src/mu-store-read.cc
@@ -78,7 +78,7 @@ mu_store_new_read_only (const char* xpath, GError **err)
 		return new _MuStore (xpath);
 
 	} catch (const MuStoreError& merr) {
-		g_set_error (err, 0, merr.mu_error(), "%s",
+		g_set_error (err, MU_ERROR_DOMAIN, merr.mu_error(), "%s",
 			     merr.what().c_str());
 
 	} MU_XAPIAN_CATCH_BLOCK_G_ERROR(err, MU_ERROR_XAPIAN);
diff --git a/src/mu-str.c b/src/mu-str.c
index fd658a37..ca1fb768 100644
--- a/src/mu-str.c
+++ b/src/mu-str.c
@@ -366,7 +366,7 @@ leave:
 	*strlst = str;
 	return g_string_free (gstr, FALSE);
 err:
-	g_set_error (err, 0, MU_ERROR_IN_PARAMETERS,
+	g_set_error (err, MU_ERROR_DOMAIN, MU_ERROR_IN_PARAMETERS,
 		     "error parsing string '%s'", g_strchug(*strlst));
 	*strlst = NULL;
 	return g_string_free (gstr, TRUE);
diff --git a/src/mu-util.c b/src/mu-util.c
index d69582e4..24c74b0f 100644
--- a/src/mu-util.c
+++ b/src/mu-util.c
@@ -137,6 +137,22 @@ mu_util_create_tmpdir (void)
 }
 
 
+GQuark
+mu_util_error_quark (void)
+{
+	static GQuark error_domain = 0;
+
+	if (G_UNLIKELY(error_domain == 0))
+		error_domain = g_quark_from_static_string
+			("mu-error-quark");
+
+	return error_domain;
+}
+
+
+
+
+
 const char*
 mu_util_cache_dir (void)
 {
diff --git a/src/mu-util.h b/src/mu-util.h
index 8d796d46..3317feea 100644
--- a/src/mu-util.h
+++ b/src/mu-util.h
@@ -185,6 +185,19 @@ gboolean mu_util_play (const char *path,
 		       gboolean allow_local, gboolean allow_remote);
 
 
+
+/**
+ * Get an error-query for mu, to be used in `g_set_error'. Recent
+ * version of Glib warn when using 0 for the error-domain in
+ * g_set_error.
+ *
+ *
+ * @return an error quark for mu
+ */
+GQuark mu_util_error_quark (void) G_GNUC_CONST;
+#define MU_ERROR_DOMAIN (mu_util_error_quark())
+
+
 /**
  * convert a string array in to a string, with the elements separated
  * by ' '